Large-scale concrete conveying equipment is used for concrete conveyance of large-scale concrete projects such as high-rise buildings, high-speed roads and overpasses. It consists of pump body and delivery pipe. This article introduces the use specifications and final work of the concrete delivery pump.
1. Specification of concrete pump
(1) The towed concrete pump can be towed by motor vehicles, but it must not carry any cargo, and the towing speed must not exceed 8km/h;
(2) The pressure of each safety valve of the hydraulic pump of the concrete pump should meet the requirements of the manual, and the user shall not adjust or change it;
(3) Construction of concrete delivery pumps in the cold season should have anti-freezing measures;
(4) During the hot season construction, the concrete delivery pump should prevent the oil temperature from being too high. When the temperature reaches 70 ℃, it should stop running or take other measures to cool down;
(5) After the pumping of concrete is completed, the hopper, S valve, concrete cylinder and conveying pipeline must be cleaned in time. After the pump is cleaned, the pressure of the accumulator should be released, the power supply should be cut off, and the switches should be in the stop or off position;
(6) Workers are not allowed to climb or ride on the pipeline, and should be absolutely avoided when working at heights;
(7) Before the pumping concrete is cleaned, it is necessary to reverse the pump several strokes to reduce the pressure in the conveying pipe and avoid causing accidents;
(8) Safety and accident prevention devices should be installed on the construction site. Such as: instructions and warning signs, fences, metal baffles, etc., set up a necessary working area (not less than 1 meter) around the pump, and non-operators shall not enter without permission. Regularly replace the conveying pipeline within three meters from the operator, must be fastened and screened with wooden boards or metal partitions;
(9) It is strictly forbidden to operate when the vacuum gauge reading is greater than 0.04Mpa, otherwise the main oil pump may be damaged;
(10) The use, installation and wiring of the electrical control box must be performed by professionals;
(11) The concrete in the hopper of the concrete delivery pump must be higher than the mixing shaft to avoid splashing of the concrete due to the suction of air;
(12) At the end of the pumping operation, when the transfer pump retracts the legs, first retract the legs, lower the ground wheels, and then retract the front legs;
(13) The operator (pumper of the concrete delivery pump) should record the work of the concrete pump as required.
(14) The concrete pump must be firmly fixed before use. Support the four feet to make the tire off the ground, or remove the tire. Check the support of the hopper and chute on the upper part of the pump to ensure stability and reliability. Pay special attention to the casualties caused by the overturning of the pump!
(15) When pumping, pay attention to concrete splash or other objects entering the eyes and causing eye injuries!
(16) The power connection of the concrete pump must have a leakage protection switch. Always check whether the original electrical appliances are working properly and whether the cable is damaged to prevent electric shock from causing casualties!
(17) To ensure the reliable connection of the conveying pipeline, regular maintenance, to prevent bursting or blockage of the pipe clamps, pipelines and cause personal injury!
(18) It is strictly forbidden to open the hydraulic pipe joints or loosen the hydraulic flange bolts when the hydraulic system is not unloaded. High-pressure hydraulic oil injection can cause great damage! (19) When the pump is in operation, it is strictly forbidden to reach into areas with moving parts such as hoppers, water tanks, reversing oil cylinders, etc. When it is necessary to check, it should be stopped and operated!
2. The end work of the concrete delivery pump
After pumping the concrete, the delivery pipeline should be cleaned immediately, the pump should be cleaned, inspection and maintenance and other finishing work should be carried out.
(1) Cleaning of transmission pipeline
Working steps of gas washing in the pipeline
a. The pipeline should be equipped with a stop valve, and the stop plate should be inserted to prevent the concrete in the vertical or upward inclined pipe from flowing back.
b. Take out some concrete from the mouth of the first straight pipe and connect it to the air wash joint. The joint should be filled with a sponge ball soaked in water in advance, and the inlet, exhaust valve and compressed air hose are installed on the joint.
c. Install a safety cover at the end of the pipeline to prevent the concrete spray from hurting people.
d. Slowly open the compressed air intake valve, so that the compressed air will push the sponge ball and concrete out. If the pipeline is equipped with a check valve, it should be opened in the open position before opening the air valve.
e. When the concrete in the pipeline has been completely emptied, and the sponge ball has also been ejected immediately, the air washing is completed. At this time, the compressed air intake valve should be closed, and then various pipe fittings should be removed.
Matters needing attention:
— The compressed air pressure shall not be higher than 0.7MPa.
—The air valve should not be opened at once, but it must be opened-closed-open. Observe carefully, and only open when the concrete can flow out smoothly.
—If you find that the purge does not work, you should first close the intake valve, then slowly open the exhaust valve to deflate, and then try to clean it in stages.
—When blowing in sections, blow off a section of the pipeline near the discharge end, and then connect the blown-out pipeline to the section that has not been blown, and blow the remaining part.
-During air washing, personnel should not be close to the outlet of the discharge, sharp turns of the pipe (if 90° bend) and compressed air pipe joints.
The washing process of the pipeline is as follows:
a. Before the end of the pumping, pump the fine stone concrete in the hopper as much as possible.
b. Reverse pump action, release the pipeline pressure, cut off the power supply.
c. Open the first section of reducing pipe and discharge door, and completely remove the residual concrete in the hopper, distribution valve box and reducing pipe.
d. Take out some concrete from the mouth of the first straight pipe and stuff it into the sponge ball soaked in water. Stuffing the cement bag paper soaked in water in front of the sponge ball also works well.
e. Connect the reducer and close the discharge door.
f. Inject water directly into the hopper.
g. Pumping.
